also, the reason for the big gain is that the 323i holds a de-tuned version of the 325i... they did agree that most N/A engines would only be able to be tuned for a small gain but this car is one of the exceptions.

I think that is likely to be right, but no guarantee! Last time I looked through the engine specs on realoem.com , I couldn't find any differences in the part numbers for the manifolds. It appears to me that both 323i and 325i get the 3-stage inlet.

It seems that is the evolve-technik tune. I'll be interested to hear your feedback.

all this scepticism is probably justified. the computer hasn't fully re-adjusted yet and the run from City Performance to my work is only a few kilometres but in the short run back to work there is a slight difference but not huge so don't think the end result is a 31kw gain. i'll take the car for a run tonight and re-asses after a couple of hundred kilometres. Mind you from 3000rpm and up it does feel a little snappier.

all this scepticism is probably justified. the computer hasn't fully re-adjusted yet and the run from City Performance to my work is only a few kilometres but in the short run back to work there is a slight difference but not huge so don't think the end result is a 31kw gain. i'll take the car for a run tonight and re-asses after a couple of hundred kilometres. Mind you from 3000rpm and up it does feel a little snappier.

There appears to be a few spots that are still yet to be filled (and I doubt everyone on that list will turn up anyway). Bmroxm5's suggestion is the best way to go as you can compare to the results of a 325i on the same machine at Advan.

What transmission do you have? You should be able to rev up to a higher rpm now if the tune is legit.

all this scepticism is probably justified. the computer hasn't fully re-adjusted yet and the run from City Performance to my work is only a few kilometres but in the short run back to work there is a slight difference but not huge so don't think the end result is a 31kw gain. i'll take the car for a run tonight and re-asses after a couple of hundred kilometres. Mind you from 3000rpm and up it does feel a little snappier.

lol maybe those living local could meet up for a coffee meet at night or on the weekend

Drawn05 - Yeah shit weather (rain + hot). took the car for a run out to Penrith and now I have done approx 150km it should all be settled.

The Verdict
There is a difference from around 3000rpm and up. The car feels like it's snappier and sharper when flooring it through the gears, but 31kw gain i'm not so sure. I must admit I haven't done alot of car mods in my time but I was expecting a bit more of a difference. To sum it up, if I had my time again I would keep my $1595 because you have to be thrashing the car to feel the moderate difference.

Over the next few weeks i'll do two things. i'll take a 325i for a test drive and compare it against mine + do a dyno at Advan Performance (is this the best place to do it?) to see the actual output. Does anyone know how much the dyno run should set me back? I can't make the group one coming up.

On the run back from penrith I did have a run (90km+) against a previous shape 330ci and whilst I wasn't in front of him he wasn't going anywhere fast.

Over the next few weeks i'll do two things. i'll take a 325i for a test drive and compare it against mine + do a dyno at Advan Performance (is this the best place to do it?) to see the actual output. Does anyone know how much the dyno run should set me back? I can't make the group one coming up.

On the run back from penrith I did have a run (90km+) against a previous shape 330ci and whilst I wasn't in front of him he wasn't going anywhere fast.

Dyno shouldn't break the bank, it depends on their time and availability really but yeh ~$50 or so.

Advan would be the best place to do it, we can compare it to the stock dyno run we did on my 325i . FYI my 325i put out 120kw at the rear wheels... it was a 6sp manual. That translates to 25% drivetrain loss from the claimed 160kw at the flywheel.

Dyno shouldn't break the bank, it depends on their time and availability really but yeh ~$50 or so.

Advan would be the best place to do it, we can compare it to the stock dyno run we did on my 325i . FYI my 325i put out 120kw at the rear wheels... it was a 6sp manual. That translates to 25% drivetrain loss from the claimed 160kw at the flywheel.